Showing papers in "Lecture Notes in Control and Information Sciences in 2004"

STRING-MAN: A novel wire robot for gait rehabilitation

Abstract: This paper presents a novel robotic prototype for advanced gait rehabilitation. This system integrates sophisticated robotic technology with control algorithms. The robot opens up new possibilities within the field of rehabilitation for restoring posture balance and gait motoric functions. The paper provides an overview of the system's fundamental components, such as the mechanical structure, patient-machine interface, sensory systems, control algorithms etc.

A wrist extension for MIT-MANUS

Abstract: In 1991, a novel robot named MIT-MANUS was introduced as a test bed to study the potential of using robots to assist in and quantify the neuro-rehabilitation of motor function. It introduced a new brand of therapy, offering a highly back-drivable mechanism with a soft and stable feel for the user. MIT-MANUS proved an excellent fit for the rehabilitation of shoulder and elbow of stroke patients with results in clinical trials showing a reduction of impairment in these joints. The greater reduction in impairment was limited to the group of muscles exercised. This suggests a need for additional robots to rehabilitate other target areas on the body. The focus here is the development and implementation of a robot for wrist rehabilitation, designed to provide three rotational degrees of freedom. This paper covers the basic system design and characteristics along with a description of therapy. We are presently conducting clinical trials at the Burke Rehabilitation Hospital (White Plains, NY). If improvemtents comparable to those seen for shoulder and elbow are seen with the wrist robot, then rehabilitation therapists will have a pair of powerful robotic tools at their disposal to promote both impairment reduction and functional independence (MIT-MANUS and wrist robot).

Experimental analysis of the proprioceptive and exteroceptive sensors of an underactuated prosthetic hand

Abstract: In general, cosmetics requirements force the engineers to incorporate the prosthetic device in a glove, and to keep size and mass of the entire device compatible with those of the human hand. The combination of robust design goals, cosmetics, and limitations of available components, can be matched only with a drastic reduction of DoFs, as compared to those of the natural hand [6]. Due to this, prostheses are characterized by low grasping functionality, and thus they do not allow adequate encirclement of objects in comparison to the human hand. This low flexibility and low adaptability of artificial fingers lead to an instability of the grasp in presence of an external perturbation, as illustrated in [7]. The development of a prosthetic hand able to replicate as much as possible the grasping and sensory features of the natural hand represents an ambitious project for scientists. State of the art technology is still far to provide engineers with components with similar performance of their natural models, and active prosthetic hands can be only a pale replication of the missing natural limb. This paper presents the current research efforts towards the development of a self-adaptative and anthropomorphic prosthetic hand. In particular, the paper is focused on the problem of replicating the natural sensory system of the hand with an artificial proprioceptive and exteroceptive sensory system. In order to enhance the dexterity of prosthetic hands by keeping an intrinsic actuation solution and a simple control algorithm, we adopted an innovative design approach based on underactuated mechanisms [8,9]. The result of these efforts is a three fingered anthropomorphic hand called RTR II hand (Figure 1) [5].

Intelligent technologies for robotic welding

Abstract: This paper discusses intelligent technologies for the robotic welding, which contains computer vision sensing, automatic programming for weld path and technical parameters, guiding and tracking seam, intelligent control of welding pool dynamics and quality. Such an welding robotic systems with some artificial intelligent functions could realize collision-free path planning for complex curve seam, detecting welding surroundings by laser scanning technology, identifying the start of weld seam and guiding weld torch, tracking the seam, complete real-time control of pulsed GTAW pool dynamical process by computer vision sensing and intelligent technology. The above intelligent separated units or subsystems were integrated into an intelligentized welding flexible manufacturing cell (IWFMC). Based on discrete event control theory and Petri net modeling method, the related domination strategies for the systems was designed to supervise the IWFMC.

Design and testing of WREX

Abstract: A passive gravity-balanced, 4 DoF arm orthosis was built for children with arm weakness such as in muscular dystrophy. The orthosis is identically gravity balanced in 3D with linear elastic elements. The orthosis has an exoskeletal configuration and is attached to the back of a wheelchair. Algorithms that yield an improved gravity-balancing scheme are derived and a new mechanical structure of the arm presented. Our experience with user trials is presented along with early results using the Jebsen test of hand function and other subjective user feedback.

Post stroke shoulder-elbow physiotherapy with industrial robots

Abstract: Robotic motor rehabilitation is a promising approach to rehabilitation of post stroke, traumatic brain injury, and spinal cord injury neuromotor impairments. We have observed that manual physiotherapy of spastic hemiparetic patients include 45 different types of three-dimensional repetitive shoulder-elbow motion exercises. The physical capabilities as well as the availability of the physiotherapist limit the realization of effective physiotherapy in daily routine. The paper describes the REHAROB Therapeutic System that uses two industrial robot arms for exercising the patient's upper limb. Special devices and measures make the system safe both for the patient and for the physiotherapist. The current REHAROB system performs individual, three-dimensional, anti-spastic passive motion therapy in the full range of concerted shoulder girdle (5) and elbow (2) motions but due to its versatility it is going to be expanded towards active assisted and active against resistance therapy, and for the physiotherapy of spastic hemiparetic lower limbs. The REHAROB Therapeutic System was designed to integrate commercially available robot, safety, control, and sensor components.

Computer vision sensing and intelligent control of welding pool dynamics

Abstract: This paper presents a successful application of intelligent technologies, such as computer vision, image processing fuzzy-neural networks, for sensing, characterization, modeling and control of the welding pool dynamic process in the pulsed Gas Tungsten Arc Welding (GTAW). The image processing algorithm is discussed in detail. The results of the 2-dimesion and 3-dimesion geometric characterization of the weld pool from the single-item pool images are presented. Neural models and self-learning neural controller for the weld pool dynamic process have been developed. The experiment results on the process indicate that the designed vision sensing and control systems are able to emulate a skilled welder's intelligent behaviors: observing, estimating, decision-making and operating. The work in the paper shows great potential and promising prospect of artificial intelligent technologies in the welding manufacturing.

Control and stabilization of the inverted pendulum via vertical forces

Abstract: In this chapter, we present a detailed analysis of the possibilities of controlling and stabilizing the inverted pendulum (IP) by means of a vertical force. First, we establish the dynamic equations of the IP under the action of a generic vertical force and then we analyze its control and stabilization. The main conclusion is that the vertical force has an excellent stabilization effect, although it requires a permanent fall of the IP support base when it is the only applied force. Therefore, we investigate the combination of the vertical force with the customary horizontal force, arriving at the stabilization conditions for different formal representations of the system: ordinary differential equations, state variable representation and Liapunov's direct and indirect methods.

Control of communication networks using infinitesimal perturbation analysis of stochastic fluid models

Abstract: 1 Dept. of Electrical and Computer Engineering, University of Cyprus, Nicosia, Cyprus, christosp@ucy.ac.cy 2 Dept. of Manufacturing Engineering and Center for Information and Systems Engineering, Boston University, Brookline, MA 02446, cgc@bu.edu 3 Dept. of Manufacturing Engineering and Center for Information and Systems Engineering, Boston University, Brookline, MA 02446, gsun@bu.edu 4 School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, wardi@ee.gatech.edu

Advances in human-friendly robotic technologies for movement: Assistance/movement restoration for people with disabilities

Abstract: Rehabilitation robots (RR) are expected to play an important role toward the independent life of older persons and persons with disabilities. Such intelligent devices, embedded into the home environment, can provide the resident with 24-hour movement assistance. Modern home-installed robots tend to be not only physically versatile in functionality but also emotionally human-friendly, i.e. they may be able to perform their functions without disturbing the user and without causing him/her any pain, inconvenience, or movement restriction, instead possibly providing him/her with comfort and pleasure. This paper analyzes the main categories of RR. The paper will then discuss some important issues of the future development of an intelligent residential space with a human-friendly rehabilitation robots integrated with it.

Toward a human-friendly user interface to control an assistive robot in the context of smart homes

Abstract: The design of robot dedicated to person with disabilities necessitates users implication in all steps of product development: design solution, prototyping the system, choice of users interfaces, and testing it with users in real conditions. However, before any design of any system, it is necessary to understand and meet the needs of the disabled users. In this chapter, we describe our research activity on the integration of a robotic arm in the environment of disabled people who have lost the abilities to use their proper arms to perform daily living tasks and who are able to use an adapted robot to compensate, even partly, the problems of manipulation in their environments. To develop a human friendly interface it is necessary to act on the system itself to make it more flexible and easy to use. Improvement of assistive robot's functionalities must comply with users environment which is composed of several assistive aids complementary to the robot. To meet this target we should have a consistent knowledge on users' needs and taking into account their specific types of disability, their restricted possibilities, and also their acceptation level of technologies. This requires multidisciplinary competencies on several research areas, such as computer sciences, networking, robotics, home automation, and also on ergonomic to provide standardized functionalities which allow efficient usability of assistive technological aids. This chapter describes the adaptation software architecture developed for an assistive robotic arm, called Manus manipulator, in the context of smart homes where the robot is considered as an object among the others.

GIVING-A-HAND system: The development of a task-specific robot appliance

Abstract: The rapidly changing demographics in industrialized nations create a pressing need for effective personal assistive aids that appeal to elderly and disabled users. Our goal is to design robotic aids that are not only affordable and commercially viable but also have universal appeal and benefit. To do so, we explore the creation of the robot appliance, a personal robotic aid with the ability to function within a localized assistive system in a specific environment within the home such as the kitchen. This chapter presents our concept of the robot appliance and details of one of two design studies involving our concept for task-specific, robotic aids. We discuss the GIVING-A-HAND system concept and the results of interviews with elderly and medium-to-high disabled persons that prioritized and refined requirements for the robotic appliance component of the system: a small, counter-top mobile robot, Addams Hand that users can remotely control to interact with common kitchen appliances to perform fetch-and-carry tasks.

Closed loop control of a load balancing network with time delays and processor resource constraints

Abstract: A deterministic dynamic nonlinear time-delay system is developed to model load balancing in a cluster of computer nodes used for parallel computations. This model refines a model previously proposed by the authors to account for the fact that the load balancing operation involves processor time which cannot be used to process tasks. Consequently, there is a trade-off between using processor time/network bandwidth and the advantage of distributing the load evenly between the nodes to reduce overall processing time. The model is shown to be self consistent in that the queue lengths cannot go negative and the total number of tasks in all the queues are conserved (i.e., load balancing can neither create nor lose tasks). It is shown that the proposed model is (Lyapunov) stable for any input, but not necessarily asymptotically stable. A closed loop controller is proposed to carry out the load balancing dynamically. Experimental results on a parallel computer network are presented to demonstrate the efficacy of the proposed load balancing strategy.

Human-friendly care robot system for the elderly

Abstract: Our care robot has walking support function for the elderly who cannot walk by themselves, and it has also various entertainment functions. It detects the direction of sound source and rotates its head toward the source. Using a CCD camera mounted on the head, it tries to find human face. If it finds human face, it moves to the human using autonomous navigation ability while avoiding obstacles. When it arrives in front of human, it stops and waits for next command. The user can give various commands using touch screen equipped robot's body. According to the commands, the robot performs walking support or various entertainment services such as for e-mail, music, movie, etc.

Position and force tracking in bilateral teleoperation

Abstract: A teleoperator is a dual robot system in which a remote slave robot tracks the motion of a master robot, which is, in turn, commanded by a human operator. To improve the task performance, information about the remote environment is needed. Feedback can be provided to the human operator by many different forms, including audio, visual displays, or tactile. However, force feedback from the slave to the master, representing contact information, provides a more extensive sense of telepresence. When this is done the teleoperator is said to be controlled bilaterally. In bilateral teleoperation, the master and the slave manipulators are coupled via a communication network and time delay is incurred in transmission of data between the master and slave site. It is well known that the delays in a closed loop system can destabilize an otherwise stable system. Time delay instability in force reflecting teleoperation was a long standing impediment to bilateral teleoperation with force feedback. The breakthrough to the bilateral teleoperation problem was achieved in [1] where concepts from Network Theory, Passivity and Scattering Theory were used to analyze mechanisms responsible for loss of stability and derive a time delay compensation scheme to guarantee stability independent of the (constant) delay. These results were then extended in [7], where the notion of wave-variables was introduced to define a new configuration for force-reflecting teleoperators. In a bilateral teleoperator, apart from the basic necessity of a stable system, there are primarily two design goals which ensure a close coupling between the human operator and the remote environment. The first goal is that the slave manipulator should track the position of the master manipulator and the second goal is that the environmental force acting on the slave, when it contacts a remote environment, be accurately transmitted to the master. It this paper we primarily address the position

Gait planning for soccer-playing humanoid robots

Abstract: Gait planning for humanoid walking and penalty kicking, the two fundamental tasks for the current humanoid soccer competition, is addressed in this paper. First, an overview of some basic research issues in the field of humanoid robotics is presented. Humanoid walking gait planning in both joint space and Cartesian space is then discussed in a detailed way so as to make a clear comparison. By introducing some new concepts such as maximum kicking range and effective kicking range, a novel gait planning method for humanoid penalty kicking is also presented. All the proposed gait synthesizing methods have been successfully implemented on a soccer-playing humanoid robot, named Robo-Erectus, developed in Singapore Polytechnic.

Cooperative welfare robot system using hand gesture instructions

Abstract: This paper explains the cooperative work system between manipulators and humans using hand gesture instructions. The goal of our system is that the manipulator can work with humans in the same working space according to the instructions of hand gestures. Our cooperative welfare robot system is composed of the manipulator, a PC and a trinocular stereovision hardware. Since the system has to recognize the position and posture of the hand in the three dimensional work space, we use the trinocular stereovision hardware. The three dimensional positions of the hand and object are obtained through range images. The gesture is recognized based on the length and width of the hand. We propose the new method in which the hand area is divided into two blocks in order to recognize the hand gesture rapidly. Through experimental results, we will show the effectiveness of our system.

Electrically assisted walker with supporter-embedded force-sensing device

Abstract: An electrically assisted walking aid with a force-sensing device embedded in its supporting arm has been developed. The force sensor consists of a pair of U-shaped members joined by four rubber springs and four gap sensors that detect the relative displacements between the members. It calculates forward and vertical forces from the displacements, and thus determines the torque about the vertical axis applied by a user. Test results showed that the sensor has sufficient precision for an electric walker.

Nd:YAG - Laser - GMA - Hybrid Welding in Shipbuilding and Steel Constructio n

Abstract: The paper dealsw ith the Nd:YAG-laser - GMA - hybrid welding process for the use in shipbuilding and steel construction. The advantages of a la- ser - arc - hybrid welding process in comparison with a laser alone or an arc alone welding process are shown. The current possibilities of the Nd:YAG-laser - GMA - hybrid welding process are shown bys ome results from hybrid welding of steel and aluminium alloys. Furthermore the advantages of the Nd:YAG-laser technol- ogy, especiall yfor a simple and flexible automation are described .The Nd:YAG- laser - GMA - hybrid welding is a process which demands a higher degree of automation in shipbuilding. Regarding to the advantages and related to the avail- able Nd:YAG-laser sources a perspective for the use of the Nd:YAG-laser tech- nology in shipbuilding and steel construction is pointed out. A current German re- search project under participation of the authors is presented in the paper. One aim of this project is to develop asystem for the automatically programming of robots and other welding systems in shipbuilding. Therefore the new programming tool should use the real geometrical data of the component before welding, resulting from a image processing tool. Concluding, the firs tmanufacturing system in ship- building (awel ding gantr yfor 12 meter T-joints) outfitted with Nd:YAG-laser - GMA - hybrid welding equipment at a German shipyard is presented. The retrofit- ting of thi sw elding gantr yhas been planned and accompanied by the company the authors are with.

27 Great Expectations for Rehabilitation Mechatronics in the Coming Decade

Abstract: This paper discusses the opportunities in the future for applications of mechatronics in rehabilitation. Trends in demographics, computer science and wireless world-circling communication portend an increasing reliance of the healthcare sector on therapy models that are consumer-driven and technology-dependent. The consumer will be at the information hub, especially in high-cost, long-duration healthcare interventions, such as those commonly found in rehabilitation, since a smaller amount of financial investment will be expected to deliver more in terms of functional outcomes. People will use computer-controlled devices like robots in assistive or exercise functions in individualized, socially embedded scenarios. Reliable sensors, adaptive motion control and robust data analysis software will change the landscape of rehabilitation practice. In the coming years, the field of robotics will be a key component to enhancing the quality of rehabilitative care and improving the communication between patient and clinical professional.

A Gentle/S approach to robot assisted neuro-rehabilitation

Abstract: Movement disorders (MD) include a group of neurological disorders that involve neuromotor systems. MD can result in several abnormalities ranging from an inability to move, to severe constant and excessive movements. Strokes are a leading cause of disability affecting largely the older people worldwide. Traditional treatments rely on the use of physiotherapy that is partially based on theories and also heavily reliant on the therapists training and past experience. The lack of evidence to prove that one treatment is more effective than any other makes the rehabilitation of stroke patients a difficult task. UL motor re-learning and recovery levels tend to improve with intensive physiotherapy delivery. The need for conclusive evidence supporting one method over the other and the need to stimulate the stroke patient clearly suggest that traditional methods lack high motivational content, as well as objective standardised analytical methods for evaluating a patient's performance and assessment of therapy effectiveness. Despite all the advances in machine mediated therapies, there is still a need to improve therapy tools. This chapter describes a new approach to robot assisted neuro-rehabilitation for upper limb rehabilitation. Gentle/S introduces a new approach on the integration of appropriate haptic technologies to high quality virtual environments, so as to deliver challenging and meaningful therapies to people with upper limb impairment in consequence of a stroke. The described approach can enhance traditional therapy tools, provide therapy "on demand" and can present accurate objective measurements of a patient's progression. Our recent studies suggest the use of tele-presence and VR-based systems can potentially motivate patients to exercise for longer periods of time. Two identical prototypes have undergone extended clinical trials in the UK and Ireland with a cohort of 30 stroke subjects. From the lessons learnt with the Gentle/S approach, it is clear also that high quality therapy devices of this nature have a role in future delivery of stroke rehabilitation, and machine mediated therapies should be available to patient and his/her clinical team from initial hospital admission, through to long term placement in the patient's home following hospital discharge.

A complete algorithm for attribute reduction

Abstract: Rough sets theory is an effective mathematical tool dealing with vagueness and uncertainty. It has been applied in a variety of fields such as data mining, pattern recognition or process control. It is significant to find high performance algorithms for attribute reduction. Most of presented algorithms were incomplete and the work on complete algorithms was comparatively little. This paper presented a complete algorithm based on the principle of discernibility matrix and discussed the time complexity of the algorithm. The proof of the completeness of the algorithm was also given in the paper. Finally, the validity of the algorithm was demonstrated by two classical databases in the UCI repository.